Poolin dashboard is divided into hashrate, workers, earnings and hashrate curve. Hashrate is total valid hashrate received by mining pool from miners. Workers refer to the number of online valid miners detected by mining pool. Earnings refer to mining profit. Units can be devided into "1 hour" and "1 day".
It is likely that multiple miners work on Miner Status, but mining pool only displays one miner online.
Please check if all miners have the same name on Miner Configuration. If the same name is changed to different names, workers can be displayed as multiple miners. (The same name for many miners will not affect your real hashrate. Hashrate is the sum of all miners hashrate.)
The format at Worker is
Sub-account Name.Miner Name